"That was very ingenious," I could not help admitting. "I must confess that the conclusions I drew from those few scribbled words were quite erroneous."
He smiled.
"You gave too much rein to your imagination. Imagination is a good servant, and a bad master. The simplest explanation is always the most likely."
"Another point--how did you know that the key of the despatch-case had been lost?"
"I did not know it. It was a guess that turned out to be correct. You observed that it had a piece of twisted wire through the handle. That suggested to me at once that it had possibly been wrenched off a flimsy key-ring. Now, if it had been lost and recovered, Mrs. Inglethorp would at once have replaced it on her bunch; but on her bunch I found what was obviously the duplicate key, very new and bright, which led me to the hypothesis that somebody else had inserted the original key in the lock of the despatch-case."
"Yes," I said, "Alfred Inglethorp, without doubt."
Poirot looked at me curiously.
"You are very sure of his guilt?"
"Well, naturally. Every fresh circumstance seems to establish it more clearly."
"On the contrary," said Poirot quietly, "there are several points in his favour."
"Oh, come now!"
"Yes."
"I see only one."
"And that?"
"That he was not in the house last night."
" 'Bad shot!' as you English say! You have chosen the one point that to my mind tells against him."
"How is that?"
"Because if Mr. Inglethorp knew that his wife would be poisoned last night, he would certainly have arranged to be away from the house. His excuse was an obviously trumped up one. That leaves us two possibilities: either he knew what was going to happen or he had a reason of his own for his absence."
"And that reason?" I asked sceptically.
Poirot shrugged his shoulders.
"How should I know? Discreditable, without doubt. This Mr. Inglethorp, I should say, is somewhat of a scoundrel--but that does not of necessity make him a murderer."
I shook my head, unconvinced.
"We do not agree, eh?" said Poirot. "Well, let us leave it. Time will show which of us is right. Now let us turn to other aspects of the case. What do you make of the fact that all the doors of the bedroom were bolted on the inside?"